1. Field of the Invention
This invention relates to measuring purchase items and more particularly relates to measuring purchase items with difficult to distinguish characteristics.
2. Description of the Related Art
Scan and bag self-checkout systems are often used to allow customers to pay for purchase items with little or no intervention from retail or store personnel. As used herein, scan and bag self-checkout systems are referred to as self-checkout systems. A customer may bring purchase items to the self-checkout system and scan each purchase item using a bar code scanner, radio frequency identifier (RFID) scanner, or the like. The customer may also place each purchase item in a bag for transporting the purchase items.
Because the customer scans his own purchase item, there is the possibility that the customer may fraudulently scan a first purchase item but actually place a second more costly purchase item in the bag. Alternatively, the customer may fraudulently or unintentionally place an un-scanned purchase item in the bag, scan a purchase item with an incorrect bar code, RFID, or the like, and/or otherwise check out purchase items that are not scanned or paid for.
Self-checkout systems may employ a scale to verify the identity of check out purchase items. For example, the self-checkout system may direct the customer to place each scanned purchase item in a bag. The bag may be in operable communication with a security scale platter that weighs the bag and the bag's contents.
For example, the security scale platter may measure the weight of the bag and the bag's contents as purchase items are added to the bag one by one. The self-checkout system may verify that each increase in the weight of the bag and contents is within an expected weight range for each added purchase item. Thus if a customer scanned a purchase item with an expected weight range of four hundred and ninety nine to five hundred and one grams (499-501 g) and the scale measured a weight increase of five hundred grams (500 g) when the purchase item is placed in the bag, the self-checkout system may verify the identity of the purchase item. However, if in this example the scale measures a weight increase of six hundred grams (600 g) when the purchase is placed in the bag, the self-checkout system may notify store personnel to intervene and manually verify the identity of the purchase item.
The security scale platter must have the capacity to measure the weight of a bag full or nearly full of potentially heavy of purchase items. Unfortunately, the security scale platter may therefore lack the resolution to distinguish purchase items with difficult to distinguish characteristics such as a light-weight purchase item. For example, the customer may scan a light-weight purchase item such as a drill bit and place the drill bit in the bag. The security scale platter may be unable to distinguish the drill bit, and the self-checkout system may notify store personnel to intervene. As a result, the customer is delayed in checking out. In addition, more store personnel on average may be required to monitor the self-checkout systems more frequently, reducing the effectiveness of the self-checkout systems.
Some self-checkout systems have reduced interventions for light-weight purchase items by not verifying the light-weight purchase items using the security scale platter. However, not verifying all purchase items may allow customers to fraudulently or unintentionally take some purchase items without being charged.
Not verifying light-weight purchase items may also undermine the security philosophy of the self-checkout system by not verifying each purchase item. Some customers may be more likely to fraudulently avoid paying for some purchase items if they learned that not all purchase items were verified. Other customers may attempt to avoid payment for light-weight purchase items simply to see if the self-checkout system could be fooled.
From the foregoing discussion, it should be apparent that a need exists for an apparatus, system, and method that measure light-weight purchase items. Beneficially, such an apparatus, system, and method would allow a self-checkout system to verify the identity of light-weight purchase items, even when the light-weight purchase items are purchased with significantly heavier items.